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The process of population ageing that has been occurring in Sweden can be expected to continue during the coming decades, the population pyramid will become increasingly rectangular, and possibly even demonstrating a shrinking base. This will lead to increasing challenges in terms of financing pensions, elderly care and healtcare. These problems will continue for at least 30 years with no demograp

The durability of a road is among other factors dependent on the affinity between stones in the top layer and bitumen that holds the stones together. Poor adherence will cause stones to detach from the surface of the road more easily. The rolling bottle method is the standard way to determine the affinity between stones and bitumen. In this test a number of stones covered in bitumen are put in a r

Historical demography, which is the study of human population dynamics in the past, is central for understanding human behaviours and traits, such as fertility, mortality and migration. An important factor in demographic research is the geographic context. Where people lived often determined their social ties, exposure to diseases and economic development. Such information is essential not only fo

Structure from sound can be phrased as the problem of determining the position of a number of microphones and a number of sound sources given only the recorded sounds. In this paper we study minimal structure from sound problems in both TOA (time of arrival) and TDOA (time difference of arrival) settings with collinear constraints on e.g. the microphone positions. Three such minimal cases are anal

The problem of estimating receiver-sender node positionsfrom measured receiver-sender distances is a key issue indifferent applications such as microphone array calibration, radioantenna array calibration, mapping and positioning using ultrawidebandand mapping and positioning using round-trip-timemeasurements between mobile phones and Wi-Fi-units. Thanks torecent research in this area we have an i

Indoor positioning for smartphone usershas received a lot of attention in recent years. Whilemany solutions have been developed, most rely on aneed for pre-deployment of infrastructure or collectingground truth data to train on. In this paper we see whatcan be done using existing WiFi-infrastructure andReceived Signal Strength from these to smartphones,not using any calibration of the signal envir

Due to advances in technology the amount of images from portable cameras has increased tremendously in recent years. Nowadays, most new mobile phones and cars have multiple cameras. Drones and other robots are often equipped with cameras as well. To be able to capture an image is not the same as to understand the content of it. Computer vision deals with the task of giving machines the ability to

Localization is an important enabling technology for many applications, such as wireless sensor networks, emergency rescue services, civil defense and transportation. Suppose that a room is equipped with several microphones (or sensors), and one person is making a sound while moving around in the room. Can one find microphone and sound source positions as well as reconstruct a room geometry? The a

Quantum mechanical weak values of projection operators have been used to answer which-way questions, e.g. to trace which arms in a multiple Mach–Zehnder setup a particle may have traversed from a given initial to a prescribed final state. I show that this procedure might lead to logical inconsistencies in the sense that different methods used to answer composite questions, like “Has the particle t

In this paper we suggest an improvement to a recent algorithm for estimating the pose and ego-motion of a camera which is constrained to planar motion at a constant height above the floor, with a constant tilt. Such motion is common in robotics applications where a camera is mounted onto a mobile platform and directed towards the floor. Due to the planar nature of the scene, images taken with such

We study and solve the previously unstudied problem of finding both sender and receiver positions from time of arrival (TOA) measurements when there is a difference in dimensionality between the affine subspaces spanned by receivers and senders. Anchor-free TOA network calibration has uses both in sound, radio and radio strength applications. Using linear techniques and requiring only a minimal nu

Fast algorithms for unequally spaced discrete Laplace transforms are presented. The algorithms are approximate up to a prescribed choice of computational precision, and they employ modified versions of algorithms for unequally spaced fast Fourier transforms using Gaussians. Various configurations of sums with equally and unequally spaced points can be dealt with. In contrast to previously presente

Intracellular beta amyloid (Aβ) accumulation is a key feature of early Alzheimer's disease (AD) and precedes the appearance of Aβ in extracellular plaques. Aβ is generated through proteolytic processing of amyloid precursor protein (APP), but the intracellular site of Aβ production is unclear. APP has been localized to multivesicular endosomes/bodies (MVBs) where sorting of APP onto ILVs could pro